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प्रश्न
Write a note on optical fibre.
उत्तर
- Transmitting signals through optical fibres is possible due to the phenomenon of total internal reflection.
- Optical fibres consists of the inner part called core and an outer part called cladding (or) sleeving.
- The refractive index of the material of the core must be higher than that of the cladding for total internal reflection to happen.
- Signal in the form of light is made to an incident inside the core-cladding boundary at an angle greater than the critical angle.
- Hence, it undergoes repeated total internal reflections along the length of the fibre without undergoing any refraction.
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